$ git clone -n https://src.fedoraproject.org/rpms/duff.git /var/lib/mock/f41-build-1072484-19725/root/chroot_tmpdir/scmroot/duff
Cloning into '/var/lib/mock/f41-build-1072484-19725/root/chroot_tmpdir/scmroot/duff'...
$ git fetch origin ae7c971032f6acaa62c8f6c38fd188bcbbf073c7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/duff
 * [new ref]         ae7c971032f6acaa62c8f6c38fd188bcbbf073c7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ae7c971 Eliminate use of obsolete %patchN syntax (#2283636)